Pan type boxes, which are used predominately in ceilings, are quite well known in the art. They are often employed when a box of limited depth is required. This occurs mainly when the electrical fixture to be installed (i.e. light, ceiling fan, etc.) is to be mounted directly underneath a ceiling joist. Hence the fixture is generally secured directly to the joist through the box. This is to be contrasted with boxes that can be used alongside a joist or between adjacent joists.
Generally, pan type boxes consist of nothing more than the box itself. They are often round and made of metal and include one or more mounting screw holes in its back wall so that a fixture fastener can pass vertically therethrough into the joist or other ceiling support. Such a box is exemplified by round ceiling fan support box bearing catalog number 56111-CFB as manufactured by The Thomas & Betts Corporation.
A variation on such a box is shown in U.S. Pat. No. 5,854,443. In this variation, two separate mounting brackets are attached to the back wall during box assembly. These mounting brackets extend upward away from the back wall and contain fastener openings therein so that a fastener can pass horizontally through the mounting bracket and into a side of the joist. The '443 patent further necessitates a second set of fasteners that secure the box to the mounting bracket and possibly even a third set of fasteners that secures the electrical fixture to the box. Hence, the load passes from one set to the other via the box and/or mounting bracket. Consequently, multiple sets of fasteners are required to properly secure a load.
Another variation is shown in U.S. Pat. No. 6,207,897. In this patent, again a pair of upright mounting brackets is secured to the back wall via a first set of fasteners during box assembly. These two brackets form a channel for receipt of a joist therein. Upon joist insertion, a second set of horizontally aligned fasteners are driven through openings in the mounting bracket into the side of the joist. Separate fasteners are then employed to secure the electrical fixture to the mounting bracket. In both this patent and the one above, the box assembly is designed so that the fixture load is transmitted via multiple fasteners sets to the mounting brackets and then to the joist itself.
One feature that is common to all such pan-style boxes described above is the material they are made of. They are all metal boxes which means they are rather expensive to manufacture and hence rather costly for a consumer to purchase.
It is thus an object of this invention to provide a pan type box that is considerably less expensive to manufacture and hence more affordable for the user. Another object of this invention is to provide a pan type box that features mounting brackets, but such brackets do not necessitate an additional assembly step as is required for the above described boxes. Still another object of this invention is to provide a pan type box that can be temporarily secured to the ceiling support without the need for a separate fastener prior to the installation of the electrical fixture. Yet another object of this invention is to reduce the number of separate fasteners required, and hence reduce costs, by requiring only fixture fasteners and no other separate set of fasteners to secure the load to the joist. These and other objects and advantages of this invention will become obvious upon further review and investigation.